Method of rendering sheet metal and sheet metal articles readily severable



y 1939- E. H. FABRICE 2,159,325

METHOD OF RENDERING SHEET METAL AND SHEET METAL ARTICLES READILY SEVERABLE Filed Sept. 30, 1935 Im/en fr ZY/wardzfZZ/Zci 2 I q p A'- i orney Patented May 23, 1939 UETED STATES PATENT OFFICE METHOD OF RENDERING SHEET METAL AND SHEET METAL ARTICLES READILY SEVER- ABLE corporation of Illinois Applicaticn September 30, 1935, Serial No. 42,858

2 Claims.

The present invention relates to a method applicable particularly to sheet metal articles such as receptacle closures, for rendering easily severable the sheet metal of which they are composed without the use of tools of any kind.

The main object of the invention is to provide a method for the purpose specified which is advantageous over methods heretofore employed for the same general purposes and, furthermore, to provide a method of this type which will render sheet metal receptacles made therefrom severable by tearing out of the same a strip or ribbon of metal without leaving burrs along the severed edges of the several resulting parts of the structure.

In the accompanying drawing illustrating receptacle for producing the same,

Fig. 1 is a fragmentary side elevation of a receptacle closure cap, such as a bottle sealing cap,

1 shown partially in section, which is equipped with a removable strip or ribbon of metal and is produced in accordance with the method of this invention.

Fig. 2 is a fragmentary perspective View, partly in section, illustrating devices employed for carrying out the method with respect to a device such as is shown in Fig. 1.

Fig. 3 is a fragmentary detail longitudinal View of the sealing cap shown in Fig. 1.

Fig. 4 is a fragmentary detail sectional view on an enlarged scale showing a piece of sheet metal partially sheared and formed in accordance with this invention to provide the same with a tear-out strip.

Fig. 5 is a view similar to Fig. 4 showing in fragmentary elevation shearing and forming rolls by means of which the metal is partially sheared and the next adjacent portions of the metal are formed.

In carrying out the invention, as, for example, in the manufacture of closure caps for bottles such as illustrated in Fig. 1, a pair of rolls A and B (as shown in Fig. 2) are employed. The roll A is equipped with what may be termed a. male annular shearing rib or band C having side edges lying in parallel planes extending perpendicularly of the longitudinal axes of said roll. The depth of said band or rib C is preferably less than the thickness of metal upon which it is intended to act.

The said roll A cooperates with the companion roll B which is equipped with an annular groove C equal in width with the band or rib C of the roll A and which is opposed to the latter, said groove C having parallel side walls disposed in the planes defining the side edges of the band or rib C of the roll A. Said groove corresponds in depth, preferably, with the depth of the rib or band C of the roll A.

Both rolls A and B are equipped with trunnions.

The said rolls A and B are suitably operated in a manner well-known to sheet metal workers to rotate simultaneously in opposite directions and, in practice, the skirt portion of the closure cap E is disposed between said rolls with the longi- M tudinal axis of the cap disposed parallel with the axes of the rolls A and B. The rolls A and B are forced toward each other during rotation as and in a manner commonly practiced in the sheet metal working art, so as to produce parallel shear cuts in the metal of the cap E, as shown in Figs. 1, 3 and 4, and at the same time force the metal bordered by said shear cuts inwardly toward the axis of the cap E a distance less than the thickness of the metal of which the cap is composed,

The annular band or strip D of metal bordered by said shear cuts constitutes what is known as a rip-strip or tear-out strip in the art of closure caps for bottles, the shear cuts efie'cting Such a ening of the metal along the side It will be noted and it is an essential feature of the invention that the strip D is offset from the body of the cap in a direction opposite to that in which it is moved in effecting its detachment from the cap for severing the latter, thereby obviating burrs along the several severance edges.

As shown in Figs. 1 to 3, the shear 'cuts are bordered by bulges of metal of the cap which form beads bordering the strip D. As the body of the cap is normally cylindrical and is made of dimensions to snugly fit a bottle neck, or the like, the said beads or bulges are effected in order to compensate for the reduction in diameter of the cap along the strip D by the inward offset of the latter from the balance of the cap, but it will be understood that the said bulges or beads may be omitted and constitute no part, feature or step of the method of this invention.

It will be obvious, of course, that the rolls A and B act simultaneously to dies to produce the 5 desired result in substantially the same manner as is true of dies.

As shown in Fig. 5, the rolls A and B are equipped with cooperating male and female shearing edges Nl and N2 of less depth than the thickness of the sheet metal of the cap. Immediately outwardly of said shearing edges N-| and N-2, said rolls are equipped with female and male formations TI and T-Z, respectively, which form the beads T in the cap bordering the rip or tear-out strip as shown in Figs. 3 and 4, said formations T-l and T2 being ogee curved in cross section.

The tongue G, which is completely severed from the body of the cap except at the end which remains integral with the rip or tear-out strip D, may be struck out by cooperating the formations on the rolls A and B or in any other suitable manner by an independent operation.

I claim as my invention:

1. The hereindescribed method of rendering severable a sheet metal sealing cap for bottles annularly thereof between its ends without leaving burrs along any of the edges of the portions of said cap severed from each other, which consists in offsetting inwardly from the circumferential faces of the cap and between the ends of the latter a strip of the metal of said cap a distance less than the thickness of the metal by partially shearing said metal along two parallel planes extending perpendicularly to the axis of the cap and completely severing one end portion of said strip of metal from the cap to provide a digitally engageable terminal tongue integral with said cap by means of which said strip of metal may be torn completely progressively outwardly of and from the body of the cap, thereby to divide the latter into three parts presenting smooth severance edges.

2. The hereindescribed method of rendering severable a closure cap for a receptacle which consists in effecting a shearing of the body of the cap between the'ends thereof in parallel planes extending perpendicularly to the axis of the cap through a depth less than the thickness of the metal of which the cap is composed and radially inwardly from the outer toward the inner face of said cap and through an arc of predetermined length and thereby offsetting inwardly from the body of the cap a strip of metal bordered by the shearing planes through a distance substantially equal to the depth of the shearing in the outer face of the cap, and completely severing out of said cap all but the base portion of a tongue, 7

said base portion being integral with one end of said strip, the tongue substantially bridging the gap between the ends of said strip.

EDWARD H. FABRICE. 

